Lathe-tool holder.



J. & W. CARR.

LATHE TOOL HOLDER.

APPLICATION FILED OUT. 2, 1907.

939,976. Patented Nev. 16.1909.

' 2 SHEETSSHEET 1.

fizz/623d 0215: 31/12 Zinzssess VLWMA 64244 haz M J. 8: W. CARR. LATHE TOOL HOLDER. APPLICATION FILED 0011.2, 1907.

Patented Nov. 16, 1909.

Z SHEETS-SHEET 2.

. m I a r i Z m UTTED SATES ATENT FFTCE.

JAMES CARR AND WILLIAM CARR, OF SYRACUSE, NEW YORK, ASSIGNORS TO THE HENRY Gr. THOMPSON 8: SON COMPANY, OF NEW HAVEN, CONNECTICUT, A COR- PORATION OF CONNECTICUT.

LATHE-TOOL HOLDER.

To all whom it may concern:

Be it known that we, JAMES CARR and nmmu CARR, of Syracuse, in the county of Onondaga, in the State of New York,

have invented new and useful Improvements ments in lathe tool holders adapted to be used in connection with the ordinary tool post for the reception and retention of specially formed tools and capable of performing any work which may be performed with any tool adapted to be used in connection with the usual tool post.

The common practice is to provide the tool with a shank adapted to be clamped in the slot of the tool post or to provide one end of a similar shank with tool holding clamps but in either case the cutting edge of the tool is almost invariably located a considerable distance from the tool post thereby allowing more or less vertical chattering or vibration of the tool, particularly in heavy cuts or castings of unequal hardness and in order to overcome this, the tool end of the shanks are usually deflected upwardly which although reducing the vibration materially, nevertheless necessitates light cuts and, therefore, prolongs the time and labor to give the article worked upon the desired finish. Furthermore, under the method now in common use it is necessary to provide separate tools for right and left hand cuts which necessitates the removal of one tool and the reinsertion of another tool into the tool post.

The main object of our present invention is to provide a tool holder adapted to embrace or fit upon the ordinary tool post and to afford a broad bearing for the tool as well as the tool holder and at the same time to enable the tool holder with the tool thereon to be reversed for right and left hand work without removing the tool from the holder or the holder from the post. The purpose in affording a broad bearing for the tool and tool holder is to prevent vertical vibration or chattering of the tool while in action.

Another object is' to provide the tool holder with a slidable key movable into and out of the slot of the tool post and adapted to be engaged by the set screw with which Specification of Letters Patent.

Application filed October 2, 1907.

Patented Nov. 16,'1909.

Serial No. 395,537.

such post is usually provided and whereby the tool holder is clamped to the tool post separately from the means which clamps the tool in the too holder so that the tool holder may be released and turned about the axis of the tool post without disturbing the adjustment of the tool thereon.

Another object is to provide the clamping key and tool holder with inter-engaging shoulders arranged so as to permit the key to be withdrawn from the tool post but still retained in the tool holder against accidental displacement thereby obviating any liability of the clamping key becoming lost or displaced.

Other objects and uses relating to specific parts of our invention will be brought out in the following description.

In the drawingsFigures 1 and 2 are respectively a top plan and a side elevation of our improved tool holder shown as operatively mounted upon an ordinary tool post. Figs. 3, 4 and 5 are sectional views taken respectively on lines 3-3, 4-4 and 55, Fig. 1. Figs. 6, 7 and S are perspective views respectively of the two clamping jaws and key of the tool holder shown in Figs. 1 to 5 inclusive.

In Figs. 1, 2, 3 and 5, we have shown an ordinary tool post -1-- as adjustably mounted in the usual manner upon a carriage 2 and provided with a transverse slot 3- and the usual set screw -t-, said carriage and tool post being shown in this instance, as provided with a bed piece or washer 5 although the latter may be dispensed with if desired, its function being simply to elevate the tool holder to the desired level.

This tool holder which forms the subject matter of our present invention consists essentially of a lower clamping jaw 6- a separate removable upper clamping jaw -7, suitable cap screws 8 for seeming the two clamping jaws together, and a key -9 adapted to be passed through the slot 3 of the tool post 1 forming with the set screw 4 a clamping device whereby the tool holder is held in place upon the carriage 2 and tool post 1.

The lower clamping jaw -6 is provided with a comparatively broad flat bottom of considerably greater diameter than the cross sectional area of the tool post around which it is adapted to be placed so as to rest firmly throughout its bottom area upon the lower portion of the carriage -2 and is provided with a pair of opposed parallel ribs -10- and ll spaced apart forming an intervening groove or key way -12 for the key -9.

As previously intimated the lower clamping jaw is provided with a central circular opening 13 extending therethrough from top to bottom for receiving the tool post, said opening being of slightly greater diameter than that of the tool post to permit the tool holder to be readily placed upon said post and removed therefrom when desired, the lengthwise groove l2 being substantially central or diametrical of the opening l3 so that when the tool holder is properly adjusted on the post, the groove l2 and key 9 will be brought into exact alinenient with the transverse slot 3- in the post.

The two clamping jaws 6 and 7 and key -9 are preferably formed of steel or case hardened iron, the lower clamping jaw being provided, in addition to the ribs l0 and ll, with an additional laterally projecting and longitudinally extending rib -1aat the base and one side of the rib 10- and provided with a transversely beveled face 15 for receiving the corresponding beveled edge of a suitable tool l6 which is clamped between said beveled face -15 and a similar beveled face -l7 on the under side of the outer edge of the upper clamping jaw 7-. These beveled clamping faces are, therefore, located wholly at one side of the tool post 1 and extend from end to end of the clamping jaws 6 and 7 so as to aiford a long bearing for the tool extending a considerable distance in opposite directions be yond the ends of the slot 3 and sides of the post l thereby reducing the liability of chattering or vertical vibration of the tool to a minimum.

The outer side of the rib -l0-and corresponding side of the upper clamping jaw 7 are disposed in vertical planes and form a suitable seat for the back of the tool -16 against which the tool is drawn by the beveled faces 15 and 17 when the upper clamping jaw is tightened by the bolts or screws 8. This upper clamping jaw 7- is also provided with a vertical opening -l9 of substantially the same size as the opening -13 in the lower clamping jaw 6 and also receives the tool post 1. The upper clamping jaw 7- is of somewhat less width than the lower clamping jaw 6 and the opening -19 is, herein, extended through one side thereof. This upper clamping jaw preferably spans or bridges across the groove -12 and rests upon the upper faces of the ribs -10 and 11, said upper clamping jaw being provided at one edge with a lengthwise rib -20 which is seated in a corresponding lengthwise groove -2lin the rib 11- of the lower clamping jaw -6 and the opposite side of the upper clamping jaw is provided with bolt openings 22 for receiving the clamping bolts -8, the ribs 20 and clamping bolts serving to secure the upper clamping jaw to the ribs -10 and ll of the lower clamping jaw at opposite sides of the groove 12 thereby tying the ribs together transversely and relieving them of considerable strain from the clamping key which looks the tool holder to the tool post and which together with the set screw l locks the tool holder and tool post to the carriage The tool side of the bottom of the lower clamping jaw G is somewhat longer than the ribs 10 and -ll and is also longer than the corresponding side of the upper clamping aw 7- to afford a long bearing, the ends of which are close to the cutting edge of the tool, thus reducing the vibration or chattering of the tool when cutting.

The clamping screws 8- enter threaded apertures 2lin the lower clamping jaw -6 at one side of the groove l2- or rather between said groove and the beveled faces l5- and 17- so as to bring the clamps as near to the tool as possible, sufficient space being left between the contiguous faces of the rib 10 and upper clamping jaw 7- to allow the tool to be tightly clamped between the bevel faces 15 and l7, the rib 20 serving as a fulcrum for the upper clamping jaw --7 during the clamping operation and at the same time establishes a lock between the two clamping aws.

In the bottom of the groove -l2 at one side of the opening -l3- is placed a stop pin 26 and secured to the under side of the key -9 near its ends are additional stop pins 27, the stop pin 26 being located between the stop pins -27-- to permit the key to be moved endwise a limited distance into and out of the slot 3 of the post lwithout liability of withdrawal or displacement so that as long as the upper clamping jaw 7- is held upon the lower clamping jaw -6 by the screws -8- the key -9- will be retained in the groove -l2-, the space between the stop pins 27 being greater than the transverse width of the slot 3 to permit the key to be entirely withdrawn from said slot when it is desired to place the tool holder upon or to remove it from the tool post.

The end faces of the tool holder are usually tapered from the tool holding side toward the opposite side to lighten its weight without sacrificing the strength and length of bearing for the tool.

In the use of our improved tool holder the upper clamping jaw and key are assembled upon the lower clamping jaw in the manner described, the key being withdrawn laterally and radially beyond one side of the opening 13- whereupon the tool holder may be placed over and upon the tool post l until it rests upon he top face of the carriage or lift block -5 whereupon the groove 12 is brought into registration with the slot 3 by simply rotating the tool holder to the desired position and the key -9 is then moved endwise through the slot -3 thereby looking the tool holder to the post. The tool 16 is then placed between the bevel faces 15 and 17 of the clamping aws, after which the clamping screws 8 are tightened to firmly lock the tool in place whereupon the tool holder is adjusted to bring the tool to the desired cutting position and is then clamped in place by the set screw 4' in the manner previously described.

When it is desired to change from right to left hand cuts or vice versa, it is simply necessary to loosen the set screw aand to rotate the tool holder and post a half turn to bring the opposite cutting end of the tool into cutting position, it being understood that both ends of the tool are usually provided with cutting edges which may be identical or dissimilar according to the work required and after the tool and its holder has been readjusted they may be readily clamped in place by the set screw "4, thereby avoiding the necessity for loosening or otherwise displacing the tool from its holder. On the other hand when it is desired to sharpen or regrind the tool it may be readily removed by simply loosening the clamping bolts 8- without disturbing the clamping screw at thereby keeping the tool holder in exactly the same position while the tool is being ground and it permits the tool to be readily replaced in the same position without readjustment of the holder.

\Vhat we claim is:

1. In combination with a tool post having a transverse slot, a support for the tool post,

lower and upper clamping jaws rotatable about and both embracing the tool post and having tool seats in one and the same side, the lower jaw having a key way movable into and out of registration with the slot, a key in said key way extending through the slot, means to engage said key to clamp the tool post and lower jaw to the support, and

separate means for clamping the upper jaw to the lower jaw.

2. In combination with a slotted tool post and support therefor, lower and upper tool clamping jaws rotatable about said post and provided with undercut tool seats in one and the same side, the lower jaw being provided with a key way and the upper jaw extending across the key way, a key movable in the key way into and out of said slot and key way, a set screw in the tool post engaging the key, and separate means for clamping the upper jaw to the lower jaw, the meeting faces of the jaws being provided with an interfitting tongue and groove.

3. In a lathe tool holder, a tool post and bed piece, the tool post being provided with a transverse slot, lower and upper separable jaws, both embracing the tool post, the lower jaw resting upon the bed piece and provided with a lengthwise key way registered with the slot in the tool post, a key in the key way and slot, a clamping screw in the tool post engaging said key and clamping it and the lower jaws to the bed piece, said jaws having under cut tool seats in one side thereof parallel with the key way, and separate means for clamping the upper jaw to the lower jaw.

a. In a lathe tool holder, a tool post having a transverse slot and threaded aperture at right angles to the slot, lower and upper jaws embracing the tool post, the lower jaw having a lengthwise key way opening downward from its upper side, a key slidable in the key way and slot, limiting stops on the key and lower jaw for limiting the sliding movement of the key into and out of the slot in the tool post, a screw in a threaded aperture in the tool post engaging the key, the upper aw engaglng the lower aw at one side of the key way and extending across said key way, and means engaging the jaws at the opposite side of the key way for clamping them together, the latter side of the jaws being provided with under cut tool seats.

5. In a lathe tool holder, lower and upper clamping jaws, the lower jaw having a lengthwise key way, said jaws having an interfitting tongue and groove at. one side of the key way and under cut tool seats at the opposite side of the key way, means for clamping said jaws together, a key slidable in the key way, and stops for limiting the sliding movement of the key in said key way.

In witness whereof we have hereunto set our hands this 25th day of September 1907.

. JAMES CAR-R.

IVILLIAM CARR.

Vitnesses:

H. E. CHASE, MILDRED M. Norr. 

